ViroPharma Inc. and Halozyme Therapeutics’ (HALO - Snapshot Report) drug Cinryze moved a step ahead with the two partners announcing positive top-line data from a mid-stage trial on the drug. The phase II study was designed to evaluate the safety, and pharmacokinetics and pharmacodynamics of the subcutaneous formulation of Cinryze in combination with Halozyme's Enhanze technology, in patients suffering from hereditary angioedema (HAE).
We note that Cinryze in the intravenous form is currently marketed worldwide as a treatment for routine prophylaxis against angioedema attacks in adolescent and adult patients with HAE.
The Enhanze technology is a proprietary drug-delivery platform, using Halozyme's recombinant human hyaluronidase enzyme (rHuPH20). This proprietary rHuPH20 enzyme facilitates the absorption and dispersion of drugs or fluids that are injected under the skin.
The study was conducted in HAE patients who were a part of a phase II trial evaluating the subcutaneous formulation of Cinryze when dosed alone. The data demonstrated that the addition of rHuPH20 led to higher maximum levels and greater systemic exposure of functional and antigenic C1 inhibitor (C1 INH) for both doses of Cinryze (1000 and 2000 units), compared to subcutaneous administration of Cinryze. Moreover, the combination of Cinryze with rHuPH20 resulted in mean functional C1 INH levels that protect against HAE attacks.
We currently have a Neutral recommendation on ViroPharma. The stock carries a Zacks #3 Rank (Hold rating) in the short-run. We believe that the use of the subcutaneous formulation of Cinryze in combination with Halozyme's Enhanze technology could improve flexibility and convenience of dosing among patients suffering from HAE, as compared to the subcutaneous delivery of Cinryze without rHuPH20.